Process for the resolution of etodolac using glucamine derivatives

Abstract

PCT No. PCT/GB95/00857 Sec. 371 Date Dec. 6, 1996 Sec. 102(e) Date Dec. 6, 1996 PCT Filed Apr. 11, 1995 PCT Pub. No. WO95/27713 PCT Pub. Date Oct. 19, 1995The subject invention pertains to a process for the resolution of etodolac comprising the use of the resolving agent glucamine or a N-(C1-4 alkyl)-glucamine. The subject invention also concerns a process for converting a single enantiomer of etodolac into the racemate. The method comprises forming all ester of the carboxylate function of the enantiomer and treating with an acid or base.

We claim: 
     
       1. A process for preparing a glucamine or an N-(C 1-4  alkyl glucainine salt of (S)-etodolac, comprising resolving racemic etodolac using, as the resolving agent, glucamine or an N-(C 1-4  alkyl)-glucamine. 
     
     
       2. The process according to claim 1, wherein the resolving agent is meglumine. 
     
     
       3. The process according to claim 1, which is conducted in an alcoholic solvent. 
     
     
       4. The process according to any of claim 1, which additionally comprises racemising the unwanted enantiomer by formation of an ester of the carboxylate function and then acid treatment. 
     
     
       5. A process for converting a single enantiomer of etodolac into the racemate, which comprises forming an ester of the carboxylate function of that enantiomer and treating with acid or with base. 
     
     
       6. The process according to claim 5, wherein the ester is treated with acid.